Surface charge tailoring strategy using SiC doped bowl shaped spacer

For high voltage direct current (HVDC) gas-insulated substations (GIS) and gas-insulated transmission lines (GILs), the cone-type spacer is a challenging part. The surface charge accumulation on spacers is one of the most unfavorable factors that could result in unstable surface conditions. In this study, a way to dissipate the partially concentrated surface charge with nonlinear material SiC is verified by electrical simulation. The results show that the electric field distributes more evenly and the surface charge density becomes lower due to the doping of SiC. As the doping concentration increases, the surface charge density becomes lower. It is hoped that this work could bring a new perspective for the manufacture of cone-type spacers to reduce surface charge accumulation.